# Cis Gke V180 5.6.2

> Ensure use of VPC-native clusters (Automated)

- Skill: `cyberstrikeus/cis-gke-v180-5-6-2` (Agent Skill)
- Install (CLI): `npx skillmds@latest add cyberstrikeus/cis-gke-v180-5-6-2`
- Raw SKILL.md: https://api.skillmd.com/api/skills/cyberstrikeus/cis-gke-v180-5-6-2/raw
- Safety review: PASS (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: DevOps & Infra
- Author: cyberstrikeus (https://skillmd.com/u/cyberstrikeus)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/cyberstrikeus/cis-gke-v180-5-6-2

---


# 5.6.2 Ensure use of VPC-native clusters (Automated)

## Profile Applicability

- Level 1

## Description

Create Alias IPs for the node network CIDR range in order to subsequently configure IP-based policies and firewalling for pods. A cluster that uses Alias IPs is called a VPC-native cluster.

## Rationale

Using Alias IPs has several benefits:

- Pod IPs are reserved within the network ahead of time, which prevents conflict with other compute resources.
- The networking layer can perform anti-spoofing checks to ensure that egress traffic is not sent with arbitrary source IPs.
- Firewall controls for Pods can be applied separately from their nodes.
- Alias IPs allow Pods to directly access hosted services without using a NAT gateway.

## Impact

You cannot currently migrate an existing cluster that uses routes for Pod routing to a cluster that uses Alias IPs.

Cluster IPs for internal services remain only available from within the cluster. If you want to access a Kubernetes Service from within the VPC, but from outside of the cluster, use an internal load balancer.

## Audit

Using Google Cloud Console:

1. Go to Kubernetes Engine by visiting: https://console.cloud.google.com/kubernetes/list.
2. From the list of clusters, click on the desired cluster to open the Details page. Under the 'Networking' section, make sure 'VPC-native traffic routing' is set to 'Enabled'.

Using Command Line:
To check Alias IP is enabled for an existing cluster, first define 2 variables Cluster Name and Zone and then run the following command:

```
gcloud container clusters describe $CLUSTER_NAME --zone $COMPUTE_ZONE --format json | jq '.ipAllocationPolicy.useIpAliases'
```

The output of the above command should return

```json
{
  "useIpAliases": true
}
```

if VPC-native (using alias IP) is enabled. If VPC-native (using alias IP) is disabled, the above command will return null (`{ }`).

## Remediation

Alias IPs cannot be enabled on an existing cluster. To create a new cluster using Alias IPs, follow the instructions below.
Using Google Cloud Console:
If using Standard configuration mode:

1. Go to Kubernetes Engine by visiting: https://console.cloud.google.com/kubernetes/list.
2. Click `CREATE CLUSTER`, and select Standard configuration mode.
3. Configure your cluster as desired, then, click `Networking` under `CLUSTER` in the navigation pane.
4. In the 'VPC-native' section, leave 'Enable VPC-native (using alias IP)' selected.
5. Click CREATE.

Using Command Line
To enable Alias IP on a new cluster, run the following command:

```
gcloud container clusters create <cluster_name> --zone <compute_zone> --enable-ip-alias
```

## Default Value

By default, VPC-native (using alias IP) is enabled when you create a new cluster. The exception is clusters created before GKE version 1.21.0-gke.1500 (September 2021) using the gcloud CLI without --enable-ip-alias."

## References

1. https://cloud.google.com/kubernetes-engine/docs/how-to/alias-ips
2. https://cloud.google.com/kubernetes-engine/docs/concepts/alias-ips

## CIS Controls

| Controls Version | Control                                                                              | IG 1 | IG 2 | IG 3 |
| ---------------- | ------------------------------------------------------------------------------------ | ---- | ---- | ---- |
| v8               | 13.4 Perform Traffic Filtering Between Network Segments                              |      | x    | x    |
| v7               | 11 Secure Configuration for Network Devices, such as Firewalls, Routers and Switches |      |      |      |
| v7               | 14.1 Segment the Network Based on Sensitivity                                        |      | x    | x    |